1. Field of the Invention
The present invention relates to a foot-operated parking brake system for an automotive vehicle.
2. Description of the Prior Art
An example of a prior art foot-operated parking brake system is disclosed in Japanese Provisional Utility Model Publication No. 61-78773 which is shown in FIG. 4. In the figure, a parking brake pedal 1 is pivotally installed on a pivot 2 so as to be swingable in the opposite directions, i.e., in the forward or depressing direction "A" and in the rearward or returning direction "B" and urged in the returning direction "B" by means of an unshown return spring. The pedal 1 has a fan-shaped upper end portion 3 which is formed with ratchet teeth 4 at the arcuated upper edge thereof. A pivot 5 is installed on the fan-shaped upper end portion 3 at a location below the ratchet teeth 4 and connected with a wire 6 leading to brakes. A pawl 8 is pivotally installed on a stationary pivot 9 and urged by a spring 7 for engagement with the ratchet teeth 4. The pawl 8 is turnable in the direction "X" for disengagement from ratchet teeth 4 when a brake releasing knob 10 is pulled to turn a lever 11 in a predetermined direction. The pedal 1 is connected to a reciprocative piston rod 13 of an air damper 12 and abuttingly engageable with a stopper 14 for thereby being held in its brake released position.
With this structure, depression on the pedal 1 causes the wire 6 to be pulled for, thereby applying the brakes. The depressed pedal 1 is held in a brake applied position by interengagement of the pawl 8 and the ratchet teeth 4. In order to release the brakes, the brake releasing knob 10 is pulled to turn, by way of the lever 11, the pawl 8 in the direction "X" and thereby disengage the same from the ratchet teeth 4. In this instance, by the effect of the air damper 12, the pedal 1 does not turn forcibly and rapidly but gradually toward the brake released position, thus not being subjected to any large impact.
A problem of the prior art parking brake system is that since the pedal 1 is adapted to be held in its depressed positions, i.e., in its brake applied positions by interengagement of the pawl 8 and the ratchet teeth 4 a click-clack sound results from interengagement of the ratchet teeth 4 and the pawl 8 at any time of operation of the pedal 1. Another problem is that the air damper 12, which is employed for preventing forcible and rapid return of the pedal 1, is heavy and costly, resulting in the heavy weight and expensive cost of the parking brake.